Your bug report

#18449: "cat x >> x" error even when x is empty

which was filed against the coreutils package, has been closed.

The explanation is attached below, along with your original report.
If you require more details, please reply to 18449@debbugs.gnu.org.

-- 
18449: http://debbugs.gnu.org/cgi/bugreport.cgi?bug=18449
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